Mounting means for cutter bits

ABSTRACT

Mounting means for cutting tools of the type having an elongated shank of circular cross section, a hard cutting tip at one end and an abutment surface at the other end. The mounting means comprises a body having a forward surface, a rearward surface and a shank receiving perforation extending through the body from the forward surface to the rearward surface. The shank receiving perforation is of such diameter as to permit free rotation of the cutting tool shank therein and is of such length that the abutment end of the cutting tool shank extends beyond the rear surface of the body. The body is mounted on a driven element of a mining machine. An abutment means is provided in association with the driven element, the abutment means presenting an abutment surface cooperating with the abutment surface on the cutting tool shank and spaced from the rear surface of the mounting means body.

United States Patent [151 3,695,726 Krekeler [451 Oct. 3, 1972 MOUNTINGMEANS FOR CUTTER BITS Primary ExaminerEmest R. Purser [72] Inventor:Claude B. Krekeler, Cincinnati, Attorney-John Melville et A Ohm a [57ABSTRACT [73] sslgnee' g f f z g Machinery Mounting means for cuttingtools of the type having an elongated shank of circular cross section, ahard Flledi 3, 1971 cutting tip at one end and an abutment surface atthe other end. The mounting means comprises a body [21] Appl' 207410having a forward surface, a rearward surface and a Related US.Application Data shank receiving perforation extending through the [62]Division of Ser. No. 2,874, Jan. 14,- 1970, Pat. m gg f g gig gzg g gifi diameter as to permit free rotation of the cutting tool shanktherein and is of such length that the abutment Coll end of the cuttingtool shank extends beyond the rear E58] Fn id 299786 92 surface of thebody. The body is mounted on a driven 1e 0 re element of a miningmachina An abutment means is 56 R f Cited provided in association withthe driven element, the 1 e abutment means presenting an abutmentsurface UNITED STATES PATENTS cooperating with the abutment surface onthe cutting tool shank and spaced from the rear surface of the 3,397,0128/1968 Krekeler ..299/86 mounting means body 3,397,013 8/1968 Krekeler..299/86 3,554,605 1/ I971 Elders ..299/86 10 Claims, 6 Drawing FiguresMOUNTING MEANS FOR CUTTER BITS CROSS REFERENCE TO RELATED APPLICATIONThis is a divisional application of US. Pat. Application Ser. No. 2,874,filed Jan. 14, 1970, now U.S. Pat. No. 3,627,381, in the name of thesame inventor, Claude B. Krekeler, and entitled MOUNTING MEANS FORCUTTER BITS.

BACKGROUND OF THE INVENTION 1 Field of the Invention The inventionrelates to an improved means for mounting cutting tools on the drivenelements of mining machines and the like, and more particularly toimproved means for mounting cutting tools of the type having anelongated shank of circular cross section with a cutting means at oneend and an abutment surface at the other end.

2. Description of the Prior Art Recently, extensive use has been made ofpick-type bits on mining machines and the like. Such cutter bits are oftwo general types. In one type, the cutter bits comprises an elongatedshank having a conical nose portion terminating in a cutting point. Thecutting point may comprise a tip of hard cutting alloy affixed to theconical portion the cutter bit. In some instances, the entire cutter bitmay be made of hard cutting alloy,

with or without a separate hard cutting tip. The other type of bitcomprises a conical bit element intended to be removably affixed to anadapter. The adapter includes an elongated shank portion. In one form,the bit may comprise a hollow conical member, with or without a tip ofhard cutting alloy. The adapter includes a conical nose portion at oneend of the shank, configured to be received within the hollow cutterbit. In another form, the conical cutter bit may have an internal shankconfigured to be received in a perforation in the adapter.

Bits of these general types are especially useful for heavy dutyapplications wherein the bits have a greater service life and affect abetter usage of hard alloy tips. in any of the cutting tools describedabove, the elongated shanks are adapted to be received in shankreceiving perforations in mounting means. The shanks are of circularcross section and the shank receiving perforations are of such diameteras to permit rotation of the shanks therein. In use, the cutting toolswill rotate about their long axes, the rotation being generated by themutual reaction of the cutting tools and the material being cut. Thisrotation assures even wear of the cutting tools and produces aself-sharpening effect.

ln connection with cutting tools of the type described above, means haveto be provided for determining the gauge of the cutting tools. By thisis meant that means must be provided to determine the depth to which acutting tool shank will enter the shank receiving perforation in amounting means. In prior art structures, a forward abutment means wasnormally provided on the shank of the cutting tool which would contactan abutment surface in association with the forward face of a mountingmeans. Often, the forward abutment means on the shank took the form ofan annular shoulder. In some instances, the annular shoulder wasprovided with a tapering underside for engagement in a correspondingcounter sink in the forward end of the shank receiving perforation inthe mounting means.

Cutting tools of the type described, when used on heavy duty miningmachines functioning continuously during the mining operation, aresubjected to heavier and more continuous strains. The provision of theabove mentioned forward abutment means necessitated an abrupt change indiameter in the cutting tool shank at the juncture between that portionof the shank lying within the shank receiving perforation of themounting means, and that portion lying outside of the shank receivingperforation.

It was further discovered that such changes in diameter in a cuttingtool shank constituted stress-raisers, tending to concentrate thecutting strains and tending to cause failure of the shank at theposition of a stressrasier. This was found to be true whether thechanges in diameter were toward a lesser or a greater diameter. It wasfurther found that it was particularly undesirable to havestress-raising changes in diameter in that portion of a shank which wastermed the critical zone. Since the diameter of the shank is slightlyless than the diameter of the holding means perforation (so that theshank is freely rotatable therein), there will be a forwardmost and arearwardmost area of contact between the lateral exterior surface of theshank and the corresponding interior surface of the holding meansperforation. The critical zone of the shank comprises that portionthereof extending substantially from the above mentioned rearwardmostarea of contact to a point beyond and in the immediate vicinity of theabove mentioned forwardmost area of contact.

It is taught in US. Pat. No. 3,397,0l 2 that the provision of a rearabutment surface on the cutting tool shank and an abutment surface inassociation with the shank receiving perforation of the mounting meansenabled the use of a cutting tool being free of stressraising diameterchanges, particularly in the critical zone. Such a structure furtherpermitted the use of novel and improved retaining means to preventremoval of the shank of the cutting tool from the shank receivingperforation of the mounting means. These structures have proven in thefield to be characterized by a greater strength and a longer life thanwas obtainable with prior art cutting devices.

In US. Pat. No. 3,397,013 it is taught that the useful life of the partscan be appreciably extended and wear on the parts can be appreciablyminimized by the provision of a male and female engagement between theabutment surface on the rear end of the cutting tool shank and theabutment surface in association with the shank receiving perforation ofthe mounting means. In this way, a greater area of contact between thecooperating abutment surfaces is achieved, thereby minimizing gear. Thecontact between the inside surface of the shank receiving perforation ofthe mounting means and the exterior surface of the shank of the cuttingtool is more nearly a line contact, appreciably minimizing wear on bothelements. The shank receiving perforation in the mounting means tends tomaintain its proper diameter throughout its length. Wear at the rear endof the shank receiving perforation is particularly reduced, whereby theuseful life of the shank retaining means is increased. Finally, themale-female engagement of the shank and mounting means abutment surfacesprovides a pivot point about which the shank can rotate, thus furtherminimizing the departure from parallelism between the cutting tool shankand SUMMARY OF THE INVENTION The present invention is directed primarilyto improvements in mounting means of the general type set forth in theabove mentioned patents. The mounting means of the present invention areintended to be used with cutting tools of the type comprising anelongated shank with cutting means at one end and an abutment surface atthe other end.

The mounting means of the present invention comprise a body having aforward surface and a rearward surface and a shank receiving perforationextending therethrough from the forward surface to the rearward surface.The body is afiixed to a driven element of the mining machine. Thedriven element may comprise a chain block, a cutting wheel or a cutterarm. The driven element has, in association therewith, an abutment meansproviding an abutment surface spaced from the rear surface of the bodyand adapted to cooperate with the abutment surface on the cutting tool.

In one embodiment of the present invention, the mounting means comprisesa lug affixed to a driven element. The lug has a forward extension withan abutment surface thereon, adapted to cooperate with the abutmentsurface on the cutting tool shank mounted in a similar lug positionedahead of the first mentioned lug. In another embodiment, the drivenelement will be provided with a stepped or toothed surface, the uppersurface of each tooth bearing a body having a shank receivingperforation; the forward surface of each step or tooth comprising anabutment surface. In yet another embodiment, the driven element willhave affixed thereto a body with a shank receiving perforation. Behindthe body, an upstanding abutment means will be located which may be aseparate means affixed to the driven element or which may comprise anintegral, one-piece portion of the driven element. In a finalembodiment, the driven element will have an upstanding portion with adeep V-shaped notch therein. A body with a shank receiving perforationwill be affixed to one side of the V-shaped notch, the other side of thenotch comprising the abutment surface.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary side elevationof a driven element having a plurality of lugs affixed thereto, each lughaving a forward extension with an abutment surface thereon to cooperatewith the abutment surface on the shank of the cutting tool in a luglocated in front of the first mentioned lug.

FIG. 2 is a plan view of the lug and cutting tool assembly of FIG. 1.

FIG. 3 is a fragmentary, elevational view, partly in cross section, of adriven element having a stepped or toothed configuration with a bodyhaving a shank receiving perforation mounted on the upper surface ofeach step or tooth, the forward surface of each step or tooth comprisingan abutment surface.

FIG. 4 is a plan view of an assembly similar to FIG. 3, wherein theabutment surfaces on the driven element and the bodies having shankreceiving perforations are oriented at various angularities.

FIG. 5 is a fragmentary elevational view of a driven means havingaffixed thereto a body with a shank receiving perforation and anabutment means providing an abutment surface.

FIG. 6 is an elevational view of a driven element having an upstandingportion with a deep V-shaped notch, a body with a shank receivingperforation afi'ixed to one side of the notch, the other side of thenotch comprising an abutment surface.

DESCRIPTION OF THE PREFERRED EMBODIMENTS With respect to the presentinvention, the precise type and configuration of the cutting tool, thetype of retaining means used and the configuration of the abutmentsurface on the cutting tool and on the driven element do not constitutelimitations. Substantially any of the cutting tools, abutment surfacesand retaining means taught in the above identified patents may be usedin association with the mounting means described hereinafter.

In FIG. 1, a driven element is fragmentarily shown and is generallyindicated at 1. While the driven element 1 may comprise a cutter arm orthe like, for purposes of an exemplary showing it is illustrated ascomprising a cutting wheel of the type well known in the art. Thecutting wheel has a peripheral surface 2 to which a plurality of lugsare affixed by any suitable means such as welding or the like. One lugis generally indicated at 3. The lug has a body portion 4 having aforward surface 5 and a rearward surface 6. A shank receivingperforation 7 extends through the body 4 from the forward surface 5 tothe rearward surface 6. The body portion 4 has a forward extension 8with an abutment surface 9 thereon. A second lug, identical to thatdescribed, is generally indicated at 3a. Like parts have been given likeindex numerals followed by a.

Yet another lug is fragmentarily illustrated in FIG. 1 and is generallyindicated at 3b. This lug is identical to the lugs above described andlike parts have been given like index numerals followed by b.

The lugs are located one behind the other, and it will be understoodthat lugs will be similarly arranged on the entire peripheral surface 2of the cutting wheel 1.

The lug 3 is illustrated as having a cutter bit mounted therein. Thecutter bit is generally indicated at 10. For purpose of an exemplaryshowing, the cutter bit 10 is illustrated as being of the type having ashank ll of circular cross section and an integral, tapered nose 12. Thenose l2 terminates in a hard cutting tip 13. The rear end of the shankl1 terminates in an abutment surface 14.

Again, for purposes of an exemplary showing, the cutter bit 10 is shownas having a retaining means comprising a split metal ring 15 located inan annular groove 16 in the shank 11. The split metal ring 15 may besnapped into and out of the groove 16, as described in the abovementioned patents. The outside diameter of the split metal ring 15 isgreater than the diameter of the shank receiving perforation 7, so thatwhen the ring is in position, the cutter bit 10 cannot be withdrawn fromthe shank receiving perforation 7.

The lug 3a is illustrated as having a cutter bit a mounted therein. Thiscutter bit is identical to that mounted in the lug 3, and like partshave been given like index numerals followed by a. Yet another identicalcutter bit is fragmentarily shown at 10b. The cutter bit 10b is mountedin a lug not shown) positioned ahead of the lug 3a. Like parts of thecutter bit 10b have been given like index numerals followed by b.

From FIG. 1, and the above description, it will be seen that the forwardabutment surface of a given lug is adapted to cooperate with theabutment surface on the cutting tool mounted in the lug immediately infront of the first mentioned lug. Thus, lug abutment surfaces 9a,

9 and 9b cooperate with shank abutment surfaces 14b, I

14a and 14 respectively.

In the usual practice, lugs are affixed to the driven elements of miningmachinery such as chains, wheels or cutter arms in such a way that theyare oriented at different angularities to the driven elements. In thisway, the cutting points of the various cutting tools will form a cut ofsufficient width to permit the passage of the driven elements to theextent desired. Often, even the lugs of the center cutting bits may beoriented at a slight lateral angle to the direction of motion of the bitso as to increase the natural tendency of the bit to rotate during thecutting operation.

FIG. 2 is a plan view of the lug 3 of FIG. 1. It will be noted that theforward abutment surface 9 is an arcuate surface. The provision of anarcuate surface will enable the orientation of the lugs on theperipheral surface 2 at any desired angularity. Despite the angularity,the abutment surface on a cutting tool in a given lug will find anadequate cooperating abutment surface on the next lug behind. It will beunderstood by one skilled in the art that it would be within the scopeof the invention to provide the surface 9 on each lug in the form of aplanar having an appropriate angularity with respect to the adjacentlug. This would require, however, the provision of a plurality of lugshaving abutment surfaces 9 oriented at a plurality of angularities.

FIG. 3 illustrates another embodiment of the present invention. A drivenelement is fragmentarily shown and generally indicated at 17. While thedriven element will again be described as a cutting wheel, it will beunderstood that it could constitute any form of well known miningmachine driven element such as a cutter arm or the like.

In this instance, the entire periphery of the cutting wheel is providedwith a plurality of step-like or toothlike configurations, three ofwhich are fragmentarily shown at 18, 18a and 18b respectively. Each ofthe step-like configurations has an upper surface 19, 19a and 19brespectively and a forward surface 20, 20a and 20b respectively.

The upper surfaces 19, 19a and 19b are adapted to have body members orlugs affixed thereto. Two such lugs are shown at 21 and 21a. The lug 21has a forward surface 22, a rearward surface 23, and a shank receivingperforation 24. The lug 21a is identical, and like parts have been givenlike index numerals followed by a.

While, as indicated above, the precise nature of the cutting tool doesnot constitute a limitation on the present invention, for purposes of anexemplary showing the lug 21 is illustrated as having a cutting tool(generally indicated at 25) mounted therein, the cutting tool being ofthe type comprising an adapter 26 and a conical cutter bit 27. Theadapter has a shank 28 of circular cross section. The rearward end ofthe shank terminates in a flat abutment surface 29. The forward end ofthe shank has an integral, conical nose portion 30, tapering toward theforward end thereof. The nose 30 has a portion 31 of opposite taperwhich terminates at the juncture of the shank 28 and the nose 30. Thecutter bit 27 may be made by forging, by upsetting, by a turningoperation, as a screw machine product, by powdered metallurgy and inother ways not constituting a limitation on the present invention. Boththe outer and inner surfaces of the cutter bit are conical and the bitmay be provided with a tip 32 of hard cutting alloy. The lower portion33 of the bit may be distorted at one or more places so that itsdiameter will be such as to require that the bit portion 33 be expandedin order to pass over the portion 31 of the adapter nose. This mostconveniently accomplished by placing the bit over the conical nose 30 ofthe bit adapter and driving the hit home by a hammer blow exertedthrough the use of a tool having an operating face softer than thesubstance of the hard cutting tip 32. Since the distortion of the lowerend 33 of the bit is a resilient distortion, the bit will snap in placeand be firmly held on the adapter 26.

Again, the means for retaining the adapter 26 in the shank receivingperforation 24 does not constitute a limitation on the presentinvention. For purposes of an exemplary showing, the end of the shank 28is illustrated as having a transverse perforation 34 adapted to receivea roll pin 35 (as described in the above mentioned patents). The ends ofthe roll pin 35 extend beyond the periphery of the shank 28 by adistance sufficient to prevent withdrawal of the shank from the shankreceiving perforation 24.

Again, for purposes of exemplary illustration, the lug 21a is shown ashaving a bit in every way identical to the bit 10 in FIG. 1. Like partshave been given like index numerals.

Irrespective of the type of cutting too], its precise configuration andthe retaining means used in association therewith, both of the cuttingtools 10 and 25 have rear abutment surfaces 14 and 19 respectively. Theforward surfaces 20, 20a and 20b of the tooth-like or steplike portionsof the cutting wheel are adapted to act as abutment surfaces cooperatingwith the abutment surfaces on the ends of adjacent cutting tools. Thus,the cutting tool abutment surface 14 cooperates with abutment surface20a on the cutting wheel and cutting tool abutment surface 29 cooperateswith wheel abutment surface 20.

FIG. 4 illustrates an assembly of the type described with respect toFIG. 3. A cutting wheel is fragmentarily shown and generally indicatedat 36. Three of the steplike or tooth-like configurations are shown at37, 38 and 39. The steps each have an upper surface 370, 38a and 39arespectively, and a forward or abutment surface 37b, 38b and 39brespectively. Three lugs, in every way similar to the lugs 21 and 21a ofFIG. 3, are shown at 40, 41 and 42. The purpose of FIG. 4 is toillustrate, in an exemplary manner, the way in which the various lugsmay be affixed about the periphery of the cutting wheel at varyingangles to the direction of rotation (indicated by arrow A). Lug 41 ismounted on the surface 39a in such a way that a cutting tool (not shown)mounted therein will extend in the direction of arrow A. Consequently,the cutting wheel abutment surface 38b, adapted to cooperate with theabutment surface on the cutting tool, is oriented so as to beperpendicular to the cutting direction. Lugs 40 and 42, on the otherhand, are afiixed to the cutting wheel at opposite angularities to thecutting direction A. A cutting tool (not shown) mounted in lug 40 willextend beyond the edge 36a of the cutting wheel. Similarly, a cuttingtool (not shown) mounted in the lug 42 will extend beyond the edge 36bof the cutting wheel. In order to assure proper alignment of the cuttingtool abutment surfaces and the cutting wheel abutment surfaces thecutting wheel abutment surfaces 37b and 39b will be angled transversethe cutting wheel with respect to the cutting direction A. Such anarrangement will assure that the cut made by the cutting tools about theperiphery of the cutting wheel will be of sufficient width to permitpassage of the cutting wheel and its appurtenances.

FIG. illustrates yet another embodiment of the present invention. Adriven element of the mining machine is fragmentarily shown at 43. Thedriven element may comprise a chain block, a cutting wheel or a cuttingarm. In this instance, alug or body 44 is provided having a forwardsurface 45, a rearward surface 46 and a shank receiving perforation 47.The lug may be affixed to the driven element 43 by any suitable meansincluding welding and the like.

Behind the lug or body 44 there is provided an abutment means 48. Theabutment means may be a separate member affixed as by welding or thelike to thedriven element 43, or the abutment means 48 may be anintegral, upstanding portion of the driven element. The abutment means48 has an abutment surface 49 facing the rear surface 46 of the lug orbody 44.

A cutter bitis illustrated as mounted in the shank receiving perforation47 of the lug or body 44. Again, the cutter bit may be of anyappropriate configuration. For purposes of an exemplary showing thecutter bit is illustrated as being the same as the cutter bit in FIG. 1and like parts have been given like index numerals.

When the lug or body 44 and the abutment means 48 are separate elements,to be affixed to the driven element as by welding or the like, it willbe understood that they may be arranged at any desired angularity to thecutting direction. It is only necessary to assure that the body 44 andthe abutment means 48 are properly aligned with respect to each other sothat the abutment surface 49 will coact properly with the cutting toolabutment surface 14.

Another embodiment of the present invention is illustrated in FIG. 6. Inthis instance, for purposes of an exemplary showing, the driven element(generally indicated at 50) is shown in the form of a cutter chainblock. It will be understood by one skilled in the art that theembodiment of FIG. 6 is not so limited and the construction showntherein may be applied to any type of driven element.

The block 50 has an upwardly extending body 51 having therein a deepV-shaped notch (generally indicated at 52). The V-shaped notch providestwo surfaces 53 and 54. A second body 55 is affixed by welding or thelike to the surface 53. The body 55 may have any suitable exteriorconfiguration and presents a forward surface 56 and a rearward surface57. For example, the body 55 may be made out of rod or bar stock ofcircular cross section. A shank receiving perforation 58 will beprovided in the body 55.

A cutting tool (generally indicated at 59) is illustrated as beingmounted in the shank receiving perforation 58. The cutting tool 59 issimilar to those shown in FIGS. 1-3 and 5, and comprises a shank 60, anintegral nose 61, a hard cutting tip 62 and a rear abutment surface 63.

In this instance, the cutting tool 59 is illustrated as having aretaining means similar to that described with respect to the cuttingtool 25 of FIG. 3. The shank 60 has a transverse hold (not shown), intowhich a roll pin 64 is inserted.

While it will be understood that the surface 54 may itself constitute anabutment surface on the driven element 50 adapted to cooperate with thecutting tool abutment surface 63, for purposes of an exemplary showingthe driven element 50 is illustrated as having a replaceable abutmentsurface of the type taught in the above mentioned patents. Similarreplaceable abutment surfaces may be applied to all of the embodimentsof the present invention.

As shown, the body 51 is provided with a perforation 65 extending fromthe surface 54 through the body. The perforation 65 is coaxial with theshank receiving perforation 58 and of a lesser diameter. The replaceableabutment surface (generally indicated at 66) comprises an element 67havingan abutment surface 68 thereon. The element 67 is adapted to liealong the surface 54 and has a rearwardly extending lug 69 affixedthereto. The rearwardly extending lug 69 is adapted to be received inthe perforation 65 and have a frictional engagement therein. When thesurface 68 becomes worn, the replaceable abutment means 66 may beremoved by blows to a suitable tool (not shown) inserted in theperforation 65 and located against the end of the lug 69.

In all of the embodiments above described, the shank receivingperforations will have a diameter such that the cutting tool shanks willbe freely rotatable therein. In addition, the shank receivingperforations will be oriented'in such a way that the cutting tool tipswill lie above the highest part'of the mounting means, and the axis ofthe cutter bit will lie at an angle of less than 90 to the direction ofmotion of the bit in the cutting operation so that the resultant cuttingstresses will be sustained substantially in line with the cutting toolaxis.

In all of the above described embodiments, the abutment surface on thedriven element and the abutment surface on the cutting tool may beconfigured to have a male-female engagement, as described in the abovementioned US. Pat. No. 3,397,013. For purposes of an exemplary showing,such a male-female engagement is illustrated in dotted lines in FIG. 3.

In FIG. 3, a conical abutment surface 70 is shown in dotted lines on theshank 28 of the cutting tool 25. The abutment surface 20 on the cuttingwheel is shown in dotted lines as having a cooperating conicaldepression 71.

In the same figure, the cutting tool 10 is shown in dotted lines ashaving a rear abutment surface 72 of rounded configuration. The abutmentsurface-20a on the cutting wheel is illustrated in dotted lines ashaving a rounded depression 73.

Modifications may be made in the invention without departing from thespirit of it.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:

l. A mounting means for the cutting tools of mining machines and thelike of the type having an elongated shank of circular cross section, ahard cutting tip at one end and an abutment surface at the other end,the mounting means comprising a driven element of said mining machineand a body affixed to said driven element, said driven element capableof driving said body in a cutting direction, said body having a forwardsurface, a rearward surface, and a shank receiving perforation extendingthrough the body from said forward surface to said rearward surface, theshank receiving perforation being of such diameter as to permit freerotation of the cutting tool shank therein, said shank receivingperforation being of such length that the abutment end of said cuttingtool extends beyond said rearward surface of said body, and abutmentmeans affixed to said driven element and separate from said body, saidabutment means presenting an abutment surface to cooperate with saidcutting tool abutment surface when said cutting tool is mounted in saidshank receiving perforation, said abutment means being spaced from saidrear surface of said body.

2. The structure claimed in claim 1 wherein said abutment means inassociation with said driven element comprises an upstanding memberaffixed to said driven element, said upstanding member having thereonsaid abutment surface adapted to cooperate with said cutting toolabutment surface, said abutment surface on said upstanding member facingsaid rearward surface of said body.

3. The structure claimed in claim 1 wherein said abutment surface onsaid abutment means is replaceable.

4. The structure claimed in claim 1 wherein said abutment surface onsaid abutment means is so configured as to have a male-female engagementwith said abutment surface on said cutting tool.

5. The structure claimed in claim 1 wherein said body has a forwardextension, said forward extension having an abutment surface thereonfacing forwardly of said body, whereby said abutment surface may coactwith the abutment surface on a 6. The structure claimed in claim 5wherein said abutment surface on said forward extension has an arcuateconfiguration transversely of said body.

7. The structure claimed in claim 1, including a plurality of saidbodies affixed one behind the other on said driven element, each of saidbodies having a forward extension, each of said extensions having saidabutment surface thereon, each of said abutment surfaces facing andbeing spaced from the rearward surface of the adjacent one of saidbodies.

8. The structure claimed in claim 7 wherein said driven element is acutting wheel of a mining machine.

9. The structure claimed in claim 7 wherein some at least of said bodiesare so arranged on said driven element as to have the axes of theirshank receiving perforations lying at a plurality of transverseangularities to said cutting direction, said abutment surface on saidforward extension of each body having an arcuate configurati ntransverse] of said body.

10. e structure 0 aimed in claim 7 wherein some at least of said bodiesare so arranged on said driven element as to have the axes of theirshank receiving perforations lying at a plurality of transverseangularities to said cutting direction, said abutment surface on saidforward extension of each body having at least a portion perpendicularto the axis of the shank receiving perforation of the adjacent one ofsaid bodies.

3 3 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,95,7 6 Dated October 3, 1972 In fl Claude B. Krekeler It is certifiedthat error appears in the above-identified patent and that said LettersPatent are hereby corrected as shown below:

Column 10, line 10 (line 5 of claim 5), the following material should beadded in order to complete this claim: cutting tool mounted in a similarbody affixed to said driven element ahead of said first mentioned body.

Signed and sealed this 13th day of March 1973..

(SEAL) Attest:

EDWARD M.FLETCHER,JR. I ROBERT GOTTSCHALK Attesting Officer Commissionerof Patents

1. A mounting means for the cutting tools of mining machines and thelike of the type having an elongated shank of circular cross section, ahard cutting tip at one end and an abutment surface at the other end,the mounting means comprising a driven element of said mining machineand a body affixed to said driven element, said driven element capableof driving said body in a cutting direction, said body having a forwardsurface, a rearward surface, and a shank receiving perforation extendingthrough the body from said forward surface to said rearward surface, theshank receiving perforation being of such diameter as to permit freerotation of the cutting tool shank therein, said shank receivingperforation being of such length that the abutment end of said cuttingtool extends beyond said rearward surface of said body, and abutmentmeans affixed to said driven element and separate from said body, saidabutment means presenting an abutment surface to cooperate with saidcutting tool abutment surface when said cutting tool is mounted in saidshank receiving perforation, said abutment means being spaced from saidrear surface of said body.
 2. The structure claimed in claim 1 whereinsaid abutment means in association with said driven element comprises anupstanding member affixed to said driven element, said upstanding memberhaving thereon said abutment surface adapted to cooperate with saidcutting tool abutment surface, said abutment surface on said upstandingmember facing said rearward surface of said body.
 3. The structureclaimed in claim 1 wherein said abutment surface on said abutment meansis replaceable.
 4. The structure claimed in claim 1 wherein saidabutment surface on said abutment means is so configured as to have amale-female engagement with said abutment surface on said cutting tool.5. The structure claimed in claim 1 wherein said body has a forwardextension, said forward extension having an abutment surface thereonfacing forwardly of said body, whereby said abutment surface may coactwith the abutment surface on a
 6. The structure claimed in claim 5wherein said abutment surface on said forward extension has an arcuateconfiguration transversely of said body.
 7. The structure claimed inclaim 1, including a plurality of said bodies affixed one behind theother on said driven element, each of said bodies having a forwardextension, each of said extensions having said abutment surface thereon,each of said abutment surfaces facing and being spaced from the rearwardsurface of the adjacent one of said bodies.
 8. The structure claimed inclaim 7 wherein said driven element is a cutting wheel of a miningmachine.
 9. The structure claimed in claim 7 wherein some at least ofsaid bodies are so arranged on said driven element as to have the axesof their shank receiving perforations lying at a plurality of transverseangularities to said cutting direction, said abutment surface on saidforward extension of each body having an arcuate configurationtransversely of said body.
 10. The structure claimed in claim 7 whereinsome at least of said bodies are so arranged on said driven element asto have the axes of their shank receiving perforations lying at aplurality of transverse angularities to said cutting direction, saidabutment surface on said forward extension of each body having at leasta portion perpendicular to the axis of thE shank receiving perforationof the adjacent one of said bodies.